Windows: If you've upgraded to Windows 8 but would love a tool that makes it easier to tweak the OS to your liking or puts some of Windows' most common options at your fingertips, EnhanceMy8 will do the trick.

There aren't a ton of system tweakers for Linux, but we have to give a shout out to the very useful Ubuntu Tweak. It can change tons of extra settings in Ubuntu, make applications easy to install for beginners, and clean up unnecessary files on your system.

Windows users have a ton of system tweakers to choose from, but we love the Ultimate Windows Tweaker the most. It has a ton of different tweaks you can perform, it's portable, super lightweight, and completely free.

If you want to tweak settings and run maintenance scripts in Mac OS X, you can always take it to the command line. On the other hand, you can always turn to one of the few system tweakers available to get the job done from a graphical user interface (GUI). Our favorite is OnyX for its exhaustive feature set that…